> From [log in to unmask] Sat Jul 1 05:22:43 2000
> Date: Fri, 30 Jun 2000 22:22:55 -0500
Dear Joe,
> Ran into a problem when I tried to plot fitted and adjusted responses
> against time a couple times. Despite high significance, SPM99
> indicated that no raw data had been saved at that voxel and gave me the
> option of moving to the closest point which had data; when I chose this
> option, it went to another cluster entirely. In one case, this was for
> the local maximum of the most significant cluster (better than 0.000
> uncorrected for the voxel and for the cluster). The entire area was
> grayed in on the glass brain. The default for the statistics was set
> at 0.001 so it seemed like there should not have been a problem. Am I
> doing something wrong or is this a bug? For which voxels is SPM99
> supposed to be saving raw data for?
This apparent paradox is due to the fact that the p value for a
particular T-contrast may be more significant than the default
F-contrast used to decide whether to save data in Y.mad. All I can
suggest is that you reduce you default threshold further. Note that
you can still plot fitted responses and standard error for every voxel
(but not the actual residuals thenselves unless the data are saved in Y
.mad). To do this simply decline the option to 'jump'.
I hope this helps - Karl
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